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Journal of Physical Science and Application 2012年第6期2卷 200-204页

作者： Shanese Jasper Asya Hammond Sharonda Phelps Za'Queta Eddins douglas L. Strout Department of Physical Sciences Alabama State University Montgomery AL 36101 USA

Nitrogen molecules Nx have been the subject of much recent research because of their potential as high-energy materials. Many nitrogen molecules dissociate with very low barriers, including molecules such as acyclic N4 that are essentially unbound. A number of studies have reported the ability of heteroatoms to stabilize complex nitrogen molecules. In the present study, the energetic and electronic properties of scandium（Ⅰ） and titanium（Ⅱ） complexes with N2 and N4 are calculated and discussed. Dissociation energies and singlet-triplet energies are determined by theoretical calculations using second-order perturbation theory （MP2） in conjunction with the Dunning basis sets.

关键词： Nitrogen scandium titanium high-energy materials computational chemistry.

Novel UbE2b-associated polymorphisms in an azoospermic / oligozoospermic population

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Asian Journal of Andrology 2008年第3期10卷 461-466页

作者： Ivan Huang benjamin R. Emery Greg L. Christensen Jeanine Griffin C. Matthew Peterson douglas T. Carrell Division of Reproductive Endocrinology University of Utah Health Sciences Salt LakeCity Utah 84106 USA Andrology and IVF Laboratories University of Utah Health Sciences Salt LakeCity Utah 84106 USA

Aim： To assess whether abnormalities exist in the UbE2b gene in a population of infertile human males, and to establish biologic plausibility of any discovered mutations. Methods： We carried out polymerase chain reaction （PCR） amplification and sequence analysis of the 5＇-untranslated region and six exons of the UbE2b gene, including flanking intronic regions, in a group of fertile and infertile men. Following the identification of a putative promoter region that contained single or dual triplet deletions within a 10-CGG repeat island, we evaluated the binding affinity of these identified polymorphisms as compared to the wild-type sequence to transcription factor SP1 using a DNA-protein gel shift assay. Results： There was a novel exonic single nucleotide polymorphism （SNP） noted in exon 4 in 5% of infertile men. In silico 3D modeling of the altered protein showed an innocuous isoleucine for valine substitution. There were no mutations noted within any of the other exons. Three novel intronic SNPs were identified within the fertile group, and seven novel intronic SNPs identified in the infertile group. The DNA-protein gel shift assay noted that both single CGG deletion and double CGG deletion bands had approximately twice the binding affinity compared to the wild-type for SP1. The negative control confirmed no non-specific protein binding. Conclusion- by themselves, a single or double CGG deletion is unlikely to pose biologic significance. However, such deletions in this suspected promoter region are associated with increased binding affinity for SP1, and might represent one of several factors required for alteration of UbE2b gene expression.

关键词： UbE2b SP1 spermatogenesis male infertility single nucleotide polymorphism

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文明冲突时代的世界体系

扬州大学学报（人文社会科学版） 2016年第4期20卷 37-43页

作者： [马]Karim douglas Crow 刘勇(译) 世界伊斯兰文明高等研究院马来西亚吉隆坡46302 南京师范大学马克思主义理论博士后流动站扬州大学马克思主义学院

2008年以来的全球金融危机促使人们对全球化资本主义进行新一轮的思想审视。启蒙运动给我们留下了诸多的历史遗产,现代西方政治、经济、科学和知识文化的基础都依赖于启蒙运动,在一定意义上,所有的"现代"都是启蒙运动的产物。"现代化理... 详细信息

2008年以来的全球金融危机促使人们对全球化资本主义进行新一轮的思想审视。启蒙运动给我们留下了诸多的历史遗产,现代西方政治、经济、科学和知识文化的基础都依赖于启蒙运动,在一定意义上,所有的"现代"都是启蒙运动的产物。"现代化理论"把"不发达"的第三世界发展迟缓的原因归于未演绎资本主义制度。然而在"依附理论"特别是"现代世界体系理论"看来,第三世界的"不发达"是由资本主义世界体系的结构性不平等造成的,这个世界体系目前已接近衰竭阶段。只有从全球的角度才能更好去理解、阐释"西方的兴起""资本主义的发展""欧洲霸权""大国的兴衰""东亚的奇迹"以及"中国的崛起"等历史。在追寻全球化资本主义的替代方案中,必须牢记历史揭示的压迫及人的动机和满足构成的概念。

关键词：文明冲突世界体系全球资本主义

三峡库区澎溪河回水区溶解态金属离子来源和时空分布特征分析

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环境科学 2018年第5期39卷 2117-2125页

作者：赵晓松蔚建军付莉姜伟周川李波 douglas Haffner Christopher Weisener 张磊三峡库区水环境监测与模拟国际科技合作基地重庆400716 西南大学资源环境学院重庆400716 重庆北碚区环境保护局重庆400711 加拿大温莎大学大湖环境研究中心温莎N9B3P4

以三峡库区北岸最大支流澎溪河的高阳平湖段为例,探讨随着调水方式导致的水位变化,三峡库区支流金属离子Ca、Zn、Fe、Cr、Pb、Cu和Hg等在时间、水平和垂直空间维度上的分布和动态.在2013年6月5日~2014年5月29日为期1 a的采样周期内于澎... 详细信息

以三峡库区北岸最大支流澎溪河的高阳平湖段为例,探讨随着调水方式导致的水位变化,三峡库区支流金属离子Ca、Zn、Fe、Cr、Pb、Cu和Hg等在时间、水平和垂直空间维度上的分布和动态.在2013年6月5日~2014年5月29日为期1 a的采样周期内于澎溪河长年回水区高阳平湖的4个采样点采样共21次,平均每17.3 d采集一次.水体样品分别采自水体表层(0~0.5 m)、中层和底层(底泥以上0.5 m).冬季水体不分层期间,中层样品采自水深1/2处,分层时则采自温跃层.应用RbR-80220型水质自动分析仪监测各样点水温、电导率、水深等数据.水样采用冷原子吸收法和电感耦合等离子体原子发射光谱法(ICP-AES)测定各金属质量浓度.运用Excel、SPSS软件进行数据统计分析;以Hg离子为例,利用Matlab软件构建各水位时期金属离子质量浓度分布三维柱状图.结果表明:(1)从水体可溶性金属离子质量浓度角度,澎溪河水质总体较好,Cr、Pb、Cu、Zn和Hg等离子均低于地表水环境质量标准(Gb3838-2002)Ⅲ类水质标准相应离子质量浓度;(2)在来源上,Cr、Pb和Cu等离子来源于干流回水;Fe和Zn离子来源于澎溪河内源;Hg离子来源受干流回水和内源影响.金属离子随着温度分层出现质量浓度分层现象;(3)影响高阳平湖电导率的主要物质是非金属离子.

关键词：三峡库区澎溪河回水区金属离子时空分布

background and Research Prospect of Geo-ecological Survey and Monitor in the Critical Zone of black Soil

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 126-129页

作者： LI Zhizhong WANG Daming DAI Huimin WANG Xisheng LIANG Shuai XU Jiang YANG Jiajia WANG Lei CHEN Shengbo A lecos DEMETRIADES Veronika KOPACKOVA Igor SAVIN douglas A.HOWARD Timothy FILLEY GENG Xiaoyuan Shenyang Geological Survey of China Geological Survey Shenyang 110030LiaoningChina China Geological Survey Beijing 100000China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100000China british Geological Survey Ctr Environm SciNottingham NG125GGEngland Jilin University Institute of Geology and Mineral Exploration Olympic VillageChangchun 130026JilinChina Czech Geological Survey Remote Sensing DepartmentPrague11821Czech Republic Russian Academy of Sciences Kirensky Institute of Physics Krasnoyarsk660036Russia Department of Geology Arizona State University TempeArizona85287-1404USA Purdue Univ Dept Earth Atmospher&Planetary Sci550 Stadium Mall DrW LafayetteIN 47907USA Kentville Research and Development Centre Agriculture and Agri-Food CanadaKentvilleNS B4N 1J5Cancda

The American Science journal,on the occasion of its 125 publication anniversary,in 2016,released 125 of the most challenging scientific issues(Kennedy et al.,2005)to the *** to the basics,breadth and the influence,25 of the issues which considered to be the most important were screened,including"How many people can the Earth carry?"(Stokstad,2005;Dailyg et al.,1992;Cohen,1995)and"How high will the greenhouse effect make the earth temperature?

关键词： black soils resource black soil critical zone earth critical zone

侵袭性非霍奇金淋巴瘤18F-FDG PET/CT显像的肿瘤代谢参数及放射组学特征在预测疗效和生存时间中的作用

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中华核医学与分子影像杂志 2018年第11期38卷 775-776页

作者：唐军 Aatif Parvez Noam Tau douglas Hussey Manjula Maganti Ur Metser 上海交通大学医学院附属苏州九龙医院核医学科 Joint Department of Medical Imaging Princess Margaret Cancer CentreUniversity Health Network Mount Sinai Hospital and Women's College Hospital University of Toronto

目的确定来自于F-脱氧葡萄糖(FDG) PET/CT (PET)显像的肿瘤代谢性参数和放射组学特征是否能预测侵袭性b细胞淋巴瘤患者的疗效和预后。方法经作者单位伦理委员会批准,该回顾性研究纳入82例侵袭性b细胞淋巴瘤患者,行PET显像分期。分析使... 详细信息

目的确定来自于F-脱氧葡萄糖(FDG) PET/CT (PET)显像的肿瘤代谢性参数和放射组学特征是否能预测侵袭性b细胞淋巴瘤患者的疗效和预后。方法经作者单位伦理委员会批准,该回顾性研究纳入82例侵袭性b细胞淋巴瘤患者,行PET显像分期。分析使用不同阈值获得的全身具有代表性的肿瘤部位的代谢肿瘤体积(MTV)和肿瘤放射组学特征,对获取的特征与疗效、无病生存时间(DFS)和总生存时间(OS)进行相关性分析。结果治疗结束后,66例(80.5%)患者完全缓解。与疗效相关的参数是治疗前肿瘤大于6 cm(P=0.026)、治疗后无大于1.5 cm的残余肿瘤(P=0.028)及标准摄取值(SUV)阈值取3和6时的全身MTV(P=0.015和0.009)。纹理特征均未能预测一线治疗方案的疗效,而某些纹理特征如灰阶非均匀性(GLNU)与DFS相关(P=0.013),峰度与OS相关(P=0.035)。结论侵袭性b细胞淋巴瘤患者的全身MTV与疗效相关,而肿瘤的纹理特征不能预测疗效,尽管有几个纹理特征与治疗后残余肿瘤的出现有关,也有某些纹理特征与DFS和OS有关。尚需在更多患者中进行前瞻性研究以确定这些参数的临床预测价值。

关键词： PET/CT 非霍奇金淋巴瘤纹理放射组学代谢肿瘤体积

Interleukin-7 Receptor Signaling Network:An Integrated Systems Perspective

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Cellular & Molecular Immunology 2008年第2期5卷 79-89页

作者： Megan J. Palmer Vinay S. Mahajan Lily C. Trajman Darrell J. Irvine douglas A.Lauffenburger Jianzhu Chen Department of biological Engineering Koch Institute for Integrative Cancer Research and Department of biology Massachusetts Institute of Technology Cambridge MA 02139 USA

Interleukin-7 （IL-7） is an essential cytokine for the development and homeostatic maintenance of T and b lymphocytes. binding of IL-7 to its cognate receptor, the IL-7 receptor （IL-7R）, activates multiple pathways that regulate lymphocyte survival, glucose uptake, proliferation and differentiation. There has been much interest in understanding how IL-7 receptor signaling is modulated at multiple interconnected network levels. This review examines how the strength of the signal through the IL-7 receptor is modulated in T and b cells, including the use of shared receptor components, signaling crosstalk, shared interaction domains, feedback loops, integrated gene regulation, multimerization and ligand competition. We discuss how these network control mechanisms could integrate to govern the properties of IL-7R signaling in lymphocytes in health and disease. Analysis of IL-7 receptor signaling at a network level in a systematic manner will allow for a comprehensive approach to understanding the impact of multiple signaling pathways on lymphocyte biology. Cellular ＆ Molecular Immunology.

关键词： IL-7 receptor cytokine signaling network systems biology modeling

Leaves Aqueous Extract of <i>boerhavia coccinea</i>Induces Antinociceptive Effect but Increases Nitric Oxide Production in Macrophages

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Journal of biosciences and Medicines 2020年第10期8卷 90-103页

作者： basile N. Piegang douglas A. M. Ngangoum Sorelle M. Ngassam Pius P. Tseuguem bibiane A. Wandji Desiré F. T. bomba Aliance R. Fokoua Télesphore b. Nguelefack Research Unit of Neuro-Inflammatory and Cardiovascular Pharmacology Laboratory of Animal Physiology and Phytopharmacology Faculty of Science University of Dschang Dschang Cameroon Institut Universitaire du Golf de Guinée (IUG) Institut Supérieur des Sciences Appliquées (ISA) Douala Cameroun

Pain treatment is one of the most challenging situations of the modern medicine. To overcome the actual limitations, new strategies should be developed and phytotherapy represents a promising alternative. boerhavia coccinea is a medicinal plant used for the treatment of pain. The present work was undertaken to evaluate the antinociceptive effects of crude aqueous extract of the leaves of boerhavia coccinea (AE) on acute pain and examine its mechanism of action. The analgesic effect of AE was evaluated at doses 50, 100, 200 and 400 mg/kg using the formalin-induced nociception in mice. The specific analgesic effect of AE was verified by testing its effect of AE on the sleep induced by diazepam. The anti-inflammatory effects of AE were also tested in vivo (100 and 200 mg/kg) on CFA-induced inflammation and in vitro (1 to 300 μg/ml) on the production of NO by non-activated or activated (LPS, 1 μg/l) macrophages. The effect of AE in non-stimulated macrophages was evaluated in absence and in presence of L-NAME (100 μg/ml) or dexathetasone (30 μg/ml). AE administered orally significantly (p bited both neurogenic and inflammatory phases of the formalin pain with a maximum inhibition percentage of 81% at the 1st phase and 90% at the 2nd phase, but did not show any anti-inflammatory effect. AE at 50 mg/kg increased the latency to sleep and reduced sleep duration. AE drastically (p by non-activated or activated macrophages by up to 5654%. L-NAME and dexamethasone potentiated the activation effect of AE on NO production. In conclusion, AE possess potent antinociceptive effect that is not related to any anti-inflammatory activity. Instead, this extract increases the nitric oxide production by an unknown mechanism.

关键词： boerhavia coccinea Aqueous Extract Analgesic Macrophage Nitric Oxide

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祁连山东段河流阶地的形成时代与机制探讨

地理科学 2005年第2期25卷 197-202页

作者：高红山潘保田邬光剑李吉均李炳元 douglas burbank 业渝光兰州大学西部环境教育部重点实验室和地理科学系甘肃兰州730000 中国科学院寒区旱区环境与工程研究所冰芯与寒区环境重点实验室甘肃兰州730000 中国科学院地理科学与资源研究所北京100101 Department of Geological Sciences 国土资源部青岛海洋地质研究所山东青岛266071

第四纪期间祁连山东段发育了多级洪积台地与河流阶地,它们是研究区域构造活动与气候变化良好的载体。对该区主要河流阶地序列的野外考察,利用ESR、TL、IRSL以及14C等测年方法,研究表明,第四纪期间石羊河上游的各大支流普遍发育了5-6级阶... 详细信息

第四纪期间祁连山东段发育了多级洪积台地与河流阶地,它们是研究区域构造活动与气候变化良好的载体。对该区主要河流阶地序列的野外考察,利用ESR、TL、IRSL以及14C等测年方法,研究表明,第四纪期间石羊河上游的各大支流普遍发育了5-6级阶地,其中南营村附近金塔河五级河流阶地的形成时代大致为1.24Mab.P.(T5)、0.78Mab.P.(T4)、0.14Mab.P.(T3)、0.06Mab.P.(T2)和0.01Mab.P.(T1),完全可以与该区沙沟河、黄河兰州段以及长江三峡段的阶地序列相对比。从各级阶地砾石层的堆积时代以及阶地的沉积特征分析,我们认为,即使在构造活动区域,气候变化在河流地貌演化过程之中起着重要的控制作用。

关键词：形成时代成因河流阶地祁连山东段